1. The Field of the Invention
The present invention relates to drainage catheters. More particularly, the present invention relates to a drainage catheter hub having a locking cam for securing a suture thread to maintain an anchor configuration of the distal end of the catheter and securing the position of the catheter within the patient's body.
2. The Relevant Technology
One problem often encountered in modern medicines relates to volumes of fluids that collect in a patient's tissue, body cavities, or other positions within the patient's body and that exceed normal volumes. Collected fluids can contribute to infection, exert harmful pressure on the patient's organs, or otherwise impede in proper care and recovery of a patient. Drainage catheters have long been utilized to drain such excess volumes of fluids from patient's body. Typically, the catheter is adapted to be introduced into the patient to the site where the excess fluid is accumulated. A plurality of drainage bores are positioned in the distal end of the drainage catheter to allow passage of the fluids and any materials suspended in the fluids from the volume to the drainage bore of the catheter.
The distal end of drainage catheters are typically adapted to form an anchor configuration to secure the drainage catheter in the site where the excess fluid is accumulated. However, the tissue surrounding drainage sites often does not provide a solid or reliable substrate to maintain the position of the catheter. Additionally, drainage catheter tubes are often formed from a soft resilient material that is easily deformed when pressure is exerted on the tube. As a result, the anchor configuration of the catheter is typically formed in a relatively large pigtail-type loop that provides a reliable anchor regardless of the material properties of the catheter tube and the characteristics of the surrounding tissue. The pigtail loop is formed by curling the tip of the catheter tube until it contacts a proximal position on the catheter tube. This is accomplished utilizing a suture that is threaded between the proximal position and the tip of the catheter. When the suture is foreshortened, the tip of the catheter is securely positioned relative to the proximal position on the catheter tube.
The suture is adapted to run the length of the catheter and exit at the proximal end of the catheter tube. This configuration allows the user to manipulate the suture to maintain or release the anchor configuration of the distal end of the catheter while the distal end of the catheter is positioned inside the patient. Once the anchor configuration of the distal end of the catheter has been established, the practitioner secures the suture to maintain the anchor configuration of the catheter. Otherwise, inadvertent movement of the patient could pull the suture resulting in separation between the tip of the catheter and the proximal position on the catheter tube. In conventional designs, a practitioner wraps or ties the free end of the suture around the proximal portion of the catheter or proximally positioned catheter hub. However, wrapping or tying of the suture can be somewhat inconvenient to perform. Additionally, unwrapping or untying the suture can be difficult when preparing to reposition the anchor or withdraw the drainage catheter from the patient.
A number of devices have been developed to attempt to secure the suture to maintain the anchor configuration the distal end of the drainage catheter. One device provides a catheter hub having a proximal portion and a distal portion which clamp the suture when pushed together. A number of deficiencies are presented by currently available suture securement devices. Many such devices are difficult to manipulate while manually maintaining tension on the suture thread. Additionally, such devices may provide ease in securing the suture, but are not as easily released to allow subsequent manipulation of the suture. Other devices are not intuitive to practitioners utilizing the devices which can require training or lead to improper usage of the device. Some devices do not effectively secure the suture leading to slippage or undesirable placement of the distal end of the catheter within the patient.